A first Invitation to Tender (ITT), C3S_312a was issued in 2016 for delivery of ECV products derived from Earth observations. It resulted in 9 contracts addressing 12 ECVs.

The aim of the present ITT is:

to address 10 additional ECVs not yet covered by C3S_312a, and

to consolidate and simplify the framework agreements for all 22 ECVs to be addressed in the operational phase of C3S.

Accordingly, this ITT comprises 5 Lots, which combine multiple ECVs related to atmospheric physics (Lot 1), atmospheric composition (Lot 2), ocean (Lot 3), land hydrology and cryosphere (Lot 4) and land biosphere (Lot 5). The contract duration for each Lot shall be up to 41 months and it is expected that operational production activity will run for the remaining duration of the initial C3S Service, ending mid 2021.